World Time Zone Converter (IST, EST & GMT)
Convert times between 40+ world cities with 12-hour and 24-hour formats and day-shift flags. Ideal for IST to EST, IST to GMT and calls.
24-hour format, e.g. 09:00 or 17:30.
Converted time
3:30 AM
24-hour
03:30
same day
UTC equivalent
03:30
Coordinated Universal Time
Time difference
-5h 30m
New Delhi → London
Shows standard time for all cities. Cities with daylight saving (London, New York, Berlin, Paris, Sydney, Toronto, Auckland) may be off by one hour during their DST periods. "Use current time" follows your device clock and the fixed city offsets above.
How it works
Converted = local time + (to offset − from offset). IST is UTC+5:30.
Example: 09:00 IST = 03:30 UTC = 08:30 Dubai (same day).
Last updated: June 2026
How this calculator is verified
Checked by True Calculator automated test suite on
- Formula verified against a published worked example in the automated test suite
- Edge cases (zero, negative, boundary and unit-mismatch inputs) covered by unit tests
The full verification method is on our how we verify page. Found an error? Tell us and we will re-check it.
When to Use This Calculator
Converting time between India Standard Time and other zones is a daily need for anyone with overseas clients, family or teams — IST is UTC+5:30, which means the offset is an awkward half-hour that catches people out. This converter shows the exact time in both zones at once, handles daylight-saving differences for cities like New York and London, and makes it easy to schedule calls: 10 AM IST is 4:30 AM in New York, while London runs 5 hours 30 minutes behind India. Remote workers, students applying abroad, e-commerce sellers shipping internationally and NRIs coordinating with family in India all use it to avoid the classic mistake of scheduling a meeting that falls at 2 AM for the other side.
How to Use This Calculator
- Step 1: Pick the source city from the first list, such as New Delhi, Mumbai or Bengaluru.
- Step 2: Pick the destination city from the second list, such as New York, London or Dubai.
- Step 3: Enter the time in 24-hour format, or tap 'Use current time' to fill the source city's time from your device clock.
- Step 4: Read the converted time in 12-hour and 24-hour format, the UTC equivalent, and the day shift.
Worked Example
You are in New Delhi and a colleague in New York asks for a call at 14:00 your time. Select New Delhi as the source and New York as the destination. The tool converts 14:00 IST to 03:30 the same day in New York, since IST is 10 hours 30 minutes ahead of EST. Switching the destination to London gives 08:30, because London is 5 hours 30 minutes behind IST. The UTC card shows 08:30 for both cases, and the day-shift note matters: a 23:00 IST call becomes 12:30 the same afternoon in New York, while a 20:00 New York call lands at 06:30 the next day in Delhi.
Tips and Common Mistakes
- •Tip 1: Remember that the United States and the United Kingdom observe daylight saving time, so the fixed offset used here can be off by one hour in their summer months.
- •Tip 2: For calls with the US East Coast, mornings in India are late evening in New York — check the day-shift line before scheduling.
- •Tip 3: India itself has no daylight saving, so IST offsets against other fixed zones like the Gulf (UTC+4) are stable all year.
- ✗Mistake 1: Assuming the conversion is symmetric around noon — the 10.5-hour IST offset means a morning call converts to late night on the other side, not afternoon.
- ✗Mistake 2: Scheduling calls based on a conversion done months ago without rechecking, since US and European DST changes the gap twice a year.
Expert Note
India does not observe daylight saving time, so IST is a fixed UTC+5:30 offset year-round. The US and UK shift clocks forward in summer (EDT = UTC-4, BST = UTC+1), which changes the gap with IST by one hour. Always recheck conversions around the DST transition dates (second Sunday of March and first Sunday of November in the US).
Sources and References
- •IANA Time Zone Database (tz database)
- •Government of India: Indian Standard Time notification — Department of Science and Technology
Official sources are linked so you can confirm the current rate yourself. Check the linked page for the latest notification before relying on these figures.
Frequently Asked Questions
How do I convert IST to EST?
Select India Standard Time as the from zone and New York as the to zone. IST (UTC+5:30) minus EST (UTC−5) means New York is 10 hours 30 minutes behind — 10:00 AM IST is 11:30 PM the previous day in New York.
What is the time difference between India and the UK?
London is 5 hours 30 minutes behind India. 12:00 noon IST is 6:30 AM in London.
Why might the conversion be off by an hour?
The converter uses standard time. Cities with daylight saving time — like London, New York, Berlin and Sydney — shift by one hour during their DST periods (typically April–October).
What is UTC?
UTC (Coordinated Universal Time) is the global time standard that all time zones are measured against. IST is UTC+5:30, meaning India is five and a half hours ahead of it.
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